Hyperhidrosis, which is sweating in excess of that necessitated by normal thermoregulation, is a condition that usually begins in adolescence. Any site on the body can be affected, but the sites most commonly affected are the palms, soles, and axillae. Usually this condition is idiopathic (not attributable to any specific cause) or secondary to other diseases, metabolic disorders, febrile illnesses, or medication use. Hyperhidrosis exists in 3 forms: emotionally induced, localized, or generalized. The condition often causes great emotional distress and occupational disability for the patient.
- Drysol (20% aluminum chloride hexahydrate in absolute anhydrous ethyl alcohol) is usually the most effective topical agent. Drysol should be applied nightly on dry skin with or without occlusion until a positive result is obtained, after which the intervals between applications may be lengthened. Drysol may be irritating to the skin.
- Pills used to treat hyperhidrosis include anticholinergic medications. Anticholinergics are effective because the neurotransmitter for sweat secretion is acetylcholine which stimulates the onset of sweating. Use of anticholinergics may be unappealing because their adverse effect profile includes blurry vision, dry mouth and eyes, and constipation. In addition, other systemic medications, such as sedatives and tranquilizers, venlafaxine, beta blockers, and calcium channel blockers may be beneficial.
- Iontophoresis consists of passing a direct current across the skin. There are several models available under the brand name Drionic, through their website—the models are specific to the area being treated.
- Botulinum toxin injections are effective because of their anticholinergic effects at the neuromuscular junction and in the postganglionic sympathetic cholinergic nerves in the sweat glands. They are FDA approved and sometimes covered by insurance for treatment of the axillae. The Botox efficacy lasts from 4-8 months and requires retreating on a regular basis. Palmar and plantar treatments are not FDA approved and unlikely to be covered by insurance.
In addition to pharmacologic therapy, other treatments include surgical sympathectomy, surgical excision of the affected areas, and subcutaneous liposuction. Each modality has been used effectively but both carry significant risks compared to the above treatments.